Study suggests AMD as a biomarker of frailty, aging
In a large sample of elderly U.S. residents, late age-related macular degeneration was associated with an increased risk of all-cause mortality and mortality not related to cardiovascular disease or cancer.
The study included 5,603 participants older than 40 years, selected among National Health and Nutrition Examination Survey responders between 2005 and 2008.
AMD was present in 441 participants (6.6%) at baseline examination. Retinal photographs allowed stratification of AMD status as early AMD (5.8%) and late AMD (0.8%).
Participants with AMD tended to be older, white, former smokers, normal or overweight and to have hypertension and high levels of lipids in the blood, walking disability and comorbid cardiovascular disease (CVD).
Within the time span of the study, 433 participants died. Of these, 72 (16.9%) had AMD. The mortality rate was higher among participants with AMD, but after adjusting confounding factors, only late AMD was associated with more than twice the risk of all-cause mortality and more than threefold higher risk of mortality due to causes other than CVD and cancer.
Several factors might contribute to this association, the authors said. Visual impairment may lead to falls, fractures and unintentional injuries. In addition, individuals with late AMD might suffer from many systemic comorbidities associated with age and frailty.
“Common pathogenesis, such as chronic inflammation, atherosclerosis, oxidative stress and lipid metabolism might be the main mechanism between AMD and systemic comorbidities. The implications of these findings suggest that AMD is a biomarker of frailty and aging,” the authors wrote. – by Michela Cimberle
Disclosure: The authors reported no relevant financial disclosures.